As the bosses of the Big Six energy companies are grilled by MPs, Ann
Robinson, the Director of Consumer Policy at uSwitch.com reviews the firms'
arguments for raising customers' bills

The bosses of the Big Six energy companies are appearing before a House of Commons select committee at 2.30pm on Tuesday to explain how they set their prices.

In the past month, SSE, British Gas, npower and Scottish Power have all announced price increases, some as high as 10 per cent.

The companies are likely to claim that the inflation busting increases are due to rises in network costs and in wholesale energy prices. However, Ann Robinson, the Director of Consumer Policy at uSwitch.com is not convinced.

"According to Ofgem wholesale costs have only risen by about 1.7 per cent over the last 12 months, and network costs have only risen a bit," she said. "There's a lot of explaining that needs to be done."

Mrs Robinson is also sceptical about claims by some energy providers that green taxes aimed at tackling climate change are also to blame for increasingly expensive bills.

"ECO, which is the big one [of the green tariffs] replaced the Carbon Emission Reduction Targets, and what we paid for that on gas and electricity was £52 per year, and that's exactly what's appearing on our bill now, so no, I'm not convinced that green taxes have made such a big difference," she said.

Questions have also been raised about whether the Big Six are doing enough to help customers choose the cheapest tariffs. uSwitch recently commissioned YouGov to conduct a poll of over 5,000 people on the subject. Mrs Robinson says less than half of those polled thought that the Big Six had put them on the best tariff.

One policy to tackle rising energy costs was put forward last month by Labour leader Ed Miliband - a 20 month freeze on gas and electricity bills if Labour win the 2015 general election. Critics described the policy as "populist gimmickry" and "economically illiterate" and energy companies claimed it could lead to energy shortages and even blackouts.

Mrs Robinson says such a freeze could have "a significant impact towards the end of the decade" on crucial investment by the energy companies, even if blackouts don't happen in the the short term.

"I think the companies do have a real point here. We do need to invest in new generation and if there's a prize freeze being threatened I don't think they're going to make that investment," she said.